topic Re: How do Indexes work? in Application Development and Automation Discussions

How do Indexes work?

Former Member — Thu, 19 Jul 2007 15:29:38 GMT

Hi All,

I was curious about exactly how do indexes work? Is the data in the table stored in the index format somewhere for quick retrieval?

Regards,

Karthik

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 15:33:19 GMT

When we create an index with 2 fields , it is assumed that there exists a table with those 2 fields only ignoring the rest of the fields in the main table which makes the selct statement faster..

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 15:34:51 GMT

Hey Chandra,

Thanks for the quick response. Is there anyway I can know where can I see that assumed table which is created?

Karthik

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 15:42:31 GMT

Hi,

Indexes are used alongwith the where condition in select statement to speed up the data fetches and at the same time reducing load on database by shorting out the no. of records as per requirements and prevents unnecessary records to come in picture.

Pls reward points.

Regards,

Ameet

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 15:45:49 GMT

Hi,

An insex is copy of one or more columns sorted in ascending order.

let, select f1 f2 from t1 where f1 = 'A' and f2 = 'B'. ( f1, f2 belongs to index)

Now when this statement is executed,system will find the record from index where f1 = A and f2 = B and get the corresponding row number and go to the corresponding row to the database.

As a result searching will be fast.

Reward points if helpful.

Regards.

Srikanta Gope

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 15:49:25 GMT

Well,

I think I know all the funda which you all are so patiently trying to explain. I just wanted to know whether I can see this sorted data of few fields of a table anywhere in SAP.

Regards,

Karthik

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 16:06:24 GMT

Hi Karthik,,

The created index is itself acts as a table..but not sure if it is stored anywhere with the sorted data...

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 16:08:22 GMT

Hi Chandra,

Do you have any documentation on how secondary indexes work?

Regards,

Karthik

Re: How do Indexes work?

Former Member — Thu, 19 Jul 2007 17:04:20 GMT

Actally , its works on concept of Bookmark.That is fields on which indexes r created help in searching that records fastly.